linux/security/tomoyo/util.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * security/tomoyo/util.c
   4 *
   5 * Copyright (C) 2005-2011  NTT DATA CORPORATION
   6 */
   7
   8#include <linux/slab.h>
   9#include <linux/rculist.h>
  10
  11#include "common.h"
  12
  13/* Lock for protecting policy. */
  14DEFINE_MUTEX(tomoyo_policy_lock);
  15
  16/* Has /sbin/init started? */
  17bool tomoyo_policy_loaded;
  18
  19/*
  20 * Mapping table from "enum tomoyo_mac_index" to
  21 * "enum tomoyo_mac_category_index".
  22 */
  23const u8 tomoyo_index2category[TOMOYO_MAX_MAC_INDEX] = {
  24        /* CONFIG::file group */
  25        [TOMOYO_MAC_FILE_EXECUTE]    = TOMOYO_MAC_CATEGORY_FILE,
  26        [TOMOYO_MAC_FILE_OPEN]       = TOMOYO_MAC_CATEGORY_FILE,
  27        [TOMOYO_MAC_FILE_CREATE]     = TOMOYO_MAC_CATEGORY_FILE,
  28        [TOMOYO_MAC_FILE_UNLINK]     = TOMOYO_MAC_CATEGORY_FILE,
  29        [TOMOYO_MAC_FILE_GETATTR]    = TOMOYO_MAC_CATEGORY_FILE,
  30        [TOMOYO_MAC_FILE_MKDIR]      = TOMOYO_MAC_CATEGORY_FILE,
  31        [TOMOYO_MAC_FILE_RMDIR]      = TOMOYO_MAC_CATEGORY_FILE,
  32        [TOMOYO_MAC_FILE_MKFIFO]     = TOMOYO_MAC_CATEGORY_FILE,
  33        [TOMOYO_MAC_FILE_MKSOCK]     = TOMOYO_MAC_CATEGORY_FILE,
  34        [TOMOYO_MAC_FILE_TRUNCATE]   = TOMOYO_MAC_CATEGORY_FILE,
  35        [TOMOYO_MAC_FILE_SYMLINK]    = TOMOYO_MAC_CATEGORY_FILE,
  36        [TOMOYO_MAC_FILE_MKBLOCK]    = TOMOYO_MAC_CATEGORY_FILE,
  37        [TOMOYO_MAC_FILE_MKCHAR]     = TOMOYO_MAC_CATEGORY_FILE,
  38        [TOMOYO_MAC_FILE_LINK]       = TOMOYO_MAC_CATEGORY_FILE,
  39        [TOMOYO_MAC_FILE_RENAME]     = TOMOYO_MAC_CATEGORY_FILE,
  40        [TOMOYO_MAC_FILE_CHMOD]      = TOMOYO_MAC_CATEGORY_FILE,
  41        [TOMOYO_MAC_FILE_CHOWN]      = TOMOYO_MAC_CATEGORY_FILE,
  42        [TOMOYO_MAC_FILE_CHGRP]      = TOMOYO_MAC_CATEGORY_FILE,
  43        [TOMOYO_MAC_FILE_IOCTL]      = TOMOYO_MAC_CATEGORY_FILE,
  44        [TOMOYO_MAC_FILE_CHROOT]     = TOMOYO_MAC_CATEGORY_FILE,
  45        [TOMOYO_MAC_FILE_MOUNT]      = TOMOYO_MAC_CATEGORY_FILE,
  46        [TOMOYO_MAC_FILE_UMOUNT]     = TOMOYO_MAC_CATEGORY_FILE,
  47        [TOMOYO_MAC_FILE_PIVOT_ROOT] = TOMOYO_MAC_CATEGORY_FILE,
  48        /* CONFIG::network group */
  49        [TOMOYO_MAC_NETWORK_INET_STREAM_BIND]       =
  50        TOMOYO_MAC_CATEGORY_NETWORK,
  51        [TOMOYO_MAC_NETWORK_INET_STREAM_LISTEN]     =
  52        TOMOYO_MAC_CATEGORY_NETWORK,
  53        [TOMOYO_MAC_NETWORK_INET_STREAM_CONNECT]    =
  54        TOMOYO_MAC_CATEGORY_NETWORK,
  55        [TOMOYO_MAC_NETWORK_INET_DGRAM_BIND]        =
  56        TOMOYO_MAC_CATEGORY_NETWORK,
  57        [TOMOYO_MAC_NETWORK_INET_DGRAM_SEND]        =
  58        TOMOYO_MAC_CATEGORY_NETWORK,
  59        [TOMOYO_MAC_NETWORK_INET_RAW_BIND]          =
  60        TOMOYO_MAC_CATEGORY_NETWORK,
  61        [TOMOYO_MAC_NETWORK_INET_RAW_SEND]          =
  62        TOMOYO_MAC_CATEGORY_NETWORK,
  63        [TOMOYO_MAC_NETWORK_UNIX_STREAM_BIND]       =
  64        TOMOYO_MAC_CATEGORY_NETWORK,
  65        [TOMOYO_MAC_NETWORK_UNIX_STREAM_LISTEN]     =
  66        TOMOYO_MAC_CATEGORY_NETWORK,
  67        [TOMOYO_MAC_NETWORK_UNIX_STREAM_CONNECT]    =
  68        TOMOYO_MAC_CATEGORY_NETWORK,
  69        [TOMOYO_MAC_NETWORK_UNIX_DGRAM_BIND]        =
  70        TOMOYO_MAC_CATEGORY_NETWORK,
  71        [TOMOYO_MAC_NETWORK_UNIX_DGRAM_SEND]        =
  72        TOMOYO_MAC_CATEGORY_NETWORK,
  73        [TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_BIND]    =
  74        TOMOYO_MAC_CATEGORY_NETWORK,
  75        [TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_LISTEN]  =
  76        TOMOYO_MAC_CATEGORY_NETWORK,
  77        [TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_CONNECT] =
  78        TOMOYO_MAC_CATEGORY_NETWORK,
  79        /* CONFIG::misc group */
  80        [TOMOYO_MAC_ENVIRON]         = TOMOYO_MAC_CATEGORY_MISC,
  81};
  82
  83/**
  84 * tomoyo_convert_time - Convert time_t to YYYY/MM/DD hh/mm/ss.
  85 *
  86 * @time:  Seconds since 1970/01/01 00:00:00.
  87 * @stamp: Pointer to "struct tomoyo_time".
  88 *
  89 * Returns nothing.
  90 */
  91void tomoyo_convert_time(time64_t time64, struct tomoyo_time *stamp)
  92{
  93        struct tm tm;
  94
  95        time64_to_tm(time64, 0, &tm);
  96        stamp->sec = tm.tm_sec;
  97        stamp->min = tm.tm_min;
  98        stamp->hour = tm.tm_hour;
  99        stamp->day = tm.tm_mday;
 100        stamp->month = tm.tm_mon + 1;
 101        stamp->year = tm.tm_year + 1900;
 102}
 103
 104/**
 105 * tomoyo_permstr - Find permission keywords.
 106 *
 107 * @string: String representation for permissions in foo/bar/buz format.
 108 * @keyword: Keyword to find from @string/
 109 *
 110 * Returns true if @keyword was found in @string, false otherwise.
 111 *
 112 * This function assumes that strncmp(w1, w2, strlen(w1)) != 0 if w1 != w2.
 113 */
 114bool tomoyo_permstr(const char *string, const char *keyword)
 115{
 116        const char *cp = strstr(string, keyword);
 117
 118        if (cp)
 119                return cp == string || *(cp - 1) == '/';
 120        return false;
 121}
 122
 123/**
 124 * tomoyo_read_token - Read a word from a line.
 125 *
 126 * @param: Pointer to "struct tomoyo_acl_param".
 127 *
 128 * Returns a word on success, "" otherwise.
 129 *
 130 * To allow the caller to skip NULL check, this function returns "" rather than
 131 * NULL if there is no more words to read.
 132 */
 133char *tomoyo_read_token(struct tomoyo_acl_param *param)
 134{
 135        char *pos = param->data;
 136        char *del = strchr(pos, ' ');
 137
 138        if (del)
 139                *del++ = '\0';
 140        else
 141                del = pos + strlen(pos);
 142        param->data = del;
 143        return pos;
 144}
 145
 146static bool tomoyo_correct_path2(const char *filename, const size_t len);
 147
 148/**
 149 * tomoyo_get_domainname - Read a domainname from a line.
 150 *
 151 * @param: Pointer to "struct tomoyo_acl_param".
 152 *
 153 * Returns a domainname on success, NULL otherwise.
 154 */
 155const struct tomoyo_path_info *tomoyo_get_domainname
 156(struct tomoyo_acl_param *param)
 157{
 158        char *start = param->data;
 159        char *pos = start;
 160
 161        while (*pos) {
 162                if (*pos++ != ' ' ||
 163                    tomoyo_correct_path2(pos, strchrnul(pos, ' ') - pos))
 164                        continue;
 165                *(pos - 1) = '\0';
 166                break;
 167        }
 168        param->data = pos;
 169        if (tomoyo_correct_domain(start))
 170                return tomoyo_get_name(start);
 171        return NULL;
 172}
 173
 174/**
 175 * tomoyo_parse_ulong - Parse an "unsigned long" value.
 176 *
 177 * @result: Pointer to "unsigned long".
 178 * @str:    Pointer to string to parse.
 179 *
 180 * Returns one of values in "enum tomoyo_value_type".
 181 *
 182 * The @src is updated to point the first character after the value
 183 * on success.
 184 */
 185u8 tomoyo_parse_ulong(unsigned long *result, char **str)
 186{
 187        const char *cp = *str;
 188        char *ep;
 189        int base = 10;
 190
 191        if (*cp == '0') {
 192                char c = *(cp + 1);
 193
 194                if (c == 'x' || c == 'X') {
 195                        base = 16;
 196                        cp += 2;
 197                } else if (c >= '0' && c <= '7') {
 198                        base = 8;
 199                        cp++;
 200                }
 201        }
 202        *result = simple_strtoul(cp, &ep, base);
 203        if (cp == ep)
 204                return TOMOYO_VALUE_TYPE_INVALID;
 205        *str = ep;
 206        switch (base) {
 207        case 16:
 208                return TOMOYO_VALUE_TYPE_HEXADECIMAL;
 209        case 8:
 210                return TOMOYO_VALUE_TYPE_OCTAL;
 211        default:
 212                return TOMOYO_VALUE_TYPE_DECIMAL;
 213        }
 214}
 215
 216/**
 217 * tomoyo_print_ulong - Print an "unsigned long" value.
 218 *
 219 * @buffer:     Pointer to buffer.
 220 * @buffer_len: Size of @buffer.
 221 * @value:      An "unsigned long" value.
 222 * @type:       Type of @value.
 223 *
 224 * Returns nothing.
 225 */
 226void tomoyo_print_ulong(char *buffer, const int buffer_len,
 227                        const unsigned long value, const u8 type)
 228{
 229        if (type == TOMOYO_VALUE_TYPE_DECIMAL)
 230                snprintf(buffer, buffer_len, "%lu", value);
 231        else if (type == TOMOYO_VALUE_TYPE_OCTAL)
 232                snprintf(buffer, buffer_len, "0%lo", value);
 233        else if (type == TOMOYO_VALUE_TYPE_HEXADECIMAL)
 234                snprintf(buffer, buffer_len, "0x%lX", value);
 235        else
 236                snprintf(buffer, buffer_len, "type(%u)", type);
 237}
 238
 239/**
 240 * tomoyo_parse_name_union - Parse a tomoyo_name_union.
 241 *
 242 * @param: Pointer to "struct tomoyo_acl_param".
 243 * @ptr:   Pointer to "struct tomoyo_name_union".
 244 *
 245 * Returns true on success, false otherwise.
 246 */
 247bool tomoyo_parse_name_union(struct tomoyo_acl_param *param,
 248                             struct tomoyo_name_union *ptr)
 249{
 250        char *filename;
 251
 252        if (param->data[0] == '@') {
 253                param->data++;
 254                ptr->group = tomoyo_get_group(param, TOMOYO_PATH_GROUP);
 255                return ptr->group != NULL;
 256        }
 257        filename = tomoyo_read_token(param);
 258        if (!tomoyo_correct_word(filename))
 259                return false;
 260        ptr->filename = tomoyo_get_name(filename);
 261        return ptr->filename != NULL;
 262}
 263
 264/**
 265 * tomoyo_parse_number_union - Parse a tomoyo_number_union.
 266 *
 267 * @param: Pointer to "struct tomoyo_acl_param".
 268 * @ptr:   Pointer to "struct tomoyo_number_union".
 269 *
 270 * Returns true on success, false otherwise.
 271 */
 272bool tomoyo_parse_number_union(struct tomoyo_acl_param *param,
 273                               struct tomoyo_number_union *ptr)
 274{
 275        char *data;
 276        u8 type;
 277        unsigned long v;
 278
 279        memset(ptr, 0, sizeof(*ptr));
 280        if (param->data[0] == '@') {
 281                param->data++;
 282                ptr->group = tomoyo_get_group(param, TOMOYO_NUMBER_GROUP);
 283                return ptr->group != NULL;
 284        }
 285        data = tomoyo_read_token(param);
 286        type = tomoyo_parse_ulong(&v, &data);
 287        if (type == TOMOYO_VALUE_TYPE_INVALID)
 288                return false;
 289        ptr->values[0] = v;
 290        ptr->value_type[0] = type;
 291        if (!*data) {
 292                ptr->values[1] = v;
 293                ptr->value_type[1] = type;
 294                return true;
 295        }
 296        if (*data++ != '-')
 297                return false;
 298        type = tomoyo_parse_ulong(&v, &data);
 299        if (type == TOMOYO_VALUE_TYPE_INVALID || *data || ptr->values[0] > v)
 300                return false;
 301        ptr->values[1] = v;
 302        ptr->value_type[1] = type;
 303        return true;
 304}
 305
 306/**
 307 * tomoyo_byte_range - Check whether the string is a \ooo style octal value.
 308 *
 309 * @str: Pointer to the string.
 310 *
 311 * Returns true if @str is a \ooo style octal value, false otherwise.
 312 *
 313 * TOMOYO uses \ooo style representation for 0x01 - 0x20 and 0x7F - 0xFF.
 314 * This function verifies that \ooo is in valid range.
 315 */
 316static inline bool tomoyo_byte_range(const char *str)
 317{
 318        return *str >= '0' && *str++ <= '3' &&
 319                *str >= '0' && *str++ <= '7' &&
 320                *str >= '0' && *str <= '7';
 321}
 322
 323/**
 324 * tomoyo_alphabet_char - Check whether the character is an alphabet.
 325 *
 326 * @c: The character to check.
 327 *
 328 * Returns true if @c is an alphabet character, false otherwise.
 329 */
 330static inline bool tomoyo_alphabet_char(const char c)
 331{
 332        return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
 333}
 334
 335/**
 336 * tomoyo_make_byte - Make byte value from three octal characters.
 337 *
 338 * @c1: The first character.
 339 * @c2: The second character.
 340 * @c3: The third character.
 341 *
 342 * Returns byte value.
 343 */
 344static inline u8 tomoyo_make_byte(const u8 c1, const u8 c2, const u8 c3)
 345{
 346        return ((c1 - '0') << 6) + ((c2 - '0') << 3) + (c3 - '0');
 347}
 348
 349/**
 350 * tomoyo_valid - Check whether the character is a valid char.
 351 *
 352 * @c: The character to check.
 353 *
 354 * Returns true if @c is a valid character, false otherwise.
 355 */
 356static inline bool tomoyo_valid(const unsigned char c)
 357{
 358        return c > ' ' && c < 127;
 359}
 360
 361/**
 362 * tomoyo_invalid - Check whether the character is an invalid char.
 363 *
 364 * @c: The character to check.
 365 *
 366 * Returns true if @c is an invalid character, false otherwise.
 367 */
 368static inline bool tomoyo_invalid(const unsigned char c)
 369{
 370        return c && (c <= ' ' || c >= 127);
 371}
 372
 373/**
 374 * tomoyo_str_starts - Check whether the given string starts with the given keyword.
 375 *
 376 * @src:  Pointer to pointer to the string.
 377 * @find: Pointer to the keyword.
 378 *
 379 * Returns true if @src starts with @find, false otherwise.
 380 *
 381 * The @src is updated to point the first character after the @find
 382 * if @src starts with @find.
 383 */
 384bool tomoyo_str_starts(char **src, const char *find)
 385{
 386        const int len = strlen(find);
 387        char *tmp = *src;
 388
 389        if (strncmp(tmp, find, len))
 390                return false;
 391        tmp += len;
 392        *src = tmp;
 393        return true;
 394}
 395
 396/**
 397 * tomoyo_normalize_line - Format string.
 398 *
 399 * @buffer: The line to normalize.
 400 *
 401 * Leading and trailing whitespaces are removed.
 402 * Multiple whitespaces are packed into single space.
 403 *
 404 * Returns nothing.
 405 */
 406void tomoyo_normalize_line(unsigned char *buffer)
 407{
 408        unsigned char *sp = buffer;
 409        unsigned char *dp = buffer;
 410        bool first = true;
 411
 412        while (tomoyo_invalid(*sp))
 413                sp++;
 414        while (*sp) {
 415                if (!first)
 416                        *dp++ = ' ';
 417                first = false;
 418                while (tomoyo_valid(*sp))
 419                        *dp++ = *sp++;
 420                while (tomoyo_invalid(*sp))
 421                        sp++;
 422        }
 423        *dp = '\0';
 424}
 425
 426/**
 427 * tomoyo_correct_word2 - Validate a string.
 428 *
 429 * @string: The string to check. Maybe non-'\0'-terminated.
 430 * @len:    Length of @string.
 431 *
 432 * Check whether the given string follows the naming rules.
 433 * Returns true if @string follows the naming rules, false otherwise.
 434 */
 435static bool tomoyo_correct_word2(const char *string, size_t len)
 436{
 437        u8 recursion = 20;
 438        const char *const start = string;
 439        bool in_repetition = false;
 440
 441        if (!len)
 442                goto out;
 443        while (len--) {
 444                unsigned char c = *string++;
 445
 446                if (c == '\\') {
 447                        if (!len--)
 448                                goto out;
 449                        c = *string++;
 450                        if (c >= '0' && c <= '3') {
 451                                unsigned char d;
 452                                unsigned char e;
 453
 454                                if (!len-- || !len--)
 455                                        goto out;
 456                                d = *string++;
 457                                e = *string++;
 458                                if (d < '0' || d > '7' || e < '0' || e > '7')
 459                                        goto out;
 460                                c = tomoyo_make_byte(c, d, e);
 461                                if (c <= ' ' || c >= 127)
 462                                        continue;
 463                                goto out;
 464                        }
 465                        switch (c) {
 466                        case '\\':  /* "\\" */
 467                        case '+':   /* "\+" */
 468                        case '?':   /* "\?" */
 469                        case 'x':   /* "\x" */
 470                        case 'a':   /* "\a" */
 471                        case '-':   /* "\-" */
 472                                continue;
 473                        }
 474                        if (!recursion--)
 475                                goto out;
 476                        switch (c) {
 477                        case '*':   /* "\*" */
 478                        case '@':   /* "\@" */
 479                        case '$':   /* "\$" */
 480                        case 'X':   /* "\X" */
 481                        case 'A':   /* "\A" */
 482                                continue;
 483                        case '{':   /* "/\{" */
 484                                if (string - 3 < start || *(string - 3) != '/')
 485                                        goto out;
 486                                in_repetition = true;
 487                                continue;
 488                        case '}':   /* "\}/" */
 489                                if (*string != '/')
 490                                        goto out;
 491                                if (!in_repetition)
 492                                        goto out;
 493                                in_repetition = false;
 494                                continue;
 495                        }
 496                        goto out;
 497                } else if (in_repetition && c == '/') {
 498                        goto out;
 499                } else if (c <= ' ' || c >= 127) {
 500                        goto out;
 501                }
 502        }
 503        if (in_repetition)
 504                goto out;
 505        return true;
 506 out:
 507        return false;
 508}
 509
 510/**
 511 * tomoyo_correct_word - Validate a string.
 512 *
 513 * @string: The string to check.
 514 *
 515 * Check whether the given string follows the naming rules.
 516 * Returns true if @string follows the naming rules, false otherwise.
 517 */
 518bool tomoyo_correct_word(const char *string)
 519{
 520        return tomoyo_correct_word2(string, strlen(string));
 521}
 522
 523/**
 524 * tomoyo_correct_path2 - Check whether the given pathname follows the naming rules.
 525 *
 526 * @filename: The pathname to check.
 527 * @len:      Length of @filename.
 528 *
 529 * Returns true if @filename follows the naming rules, false otherwise.
 530 */
 531static bool tomoyo_correct_path2(const char *filename, const size_t len)
 532{
 533        const char *cp1 = memchr(filename, '/', len);
 534        const char *cp2 = memchr(filename, '.', len);
 535
 536        return cp1 && (!cp2 || (cp1 < cp2)) && tomoyo_correct_word2(filename, len);
 537}
 538
 539/**
 540 * tomoyo_correct_path - Validate a pathname.
 541 *
 542 * @filename: The pathname to check.
 543 *
 544 * Check whether the given pathname follows the naming rules.
 545 * Returns true if @filename follows the naming rules, false otherwise.
 546 */
 547bool tomoyo_correct_path(const char *filename)
 548{
 549        return tomoyo_correct_path2(filename, strlen(filename));
 550}
 551
 552/**
 553 * tomoyo_correct_domain - Check whether the given domainname follows the naming rules.
 554 *
 555 * @domainname: The domainname to check.
 556 *
 557 * Returns true if @domainname follows the naming rules, false otherwise.
 558 */
 559bool tomoyo_correct_domain(const unsigned char *domainname)
 560{
 561        if (!domainname || !tomoyo_domain_def(domainname))
 562                return false;
 563        domainname = strchr(domainname, ' ');
 564        if (!domainname++)
 565                return true;
 566        while (1) {
 567                const unsigned char *cp = strchr(domainname, ' ');
 568
 569                if (!cp)
 570                        break;
 571                if (!tomoyo_correct_path2(domainname, cp - domainname))
 572                        return false;
 573                domainname = cp + 1;
 574        }
 575        return tomoyo_correct_path(domainname);
 576}
 577
 578/**
 579 * tomoyo_domain_def - Check whether the given token can be a domainname.
 580 *
 581 * @buffer: The token to check.
 582 *
 583 * Returns true if @buffer possibly be a domainname, false otherwise.
 584 */
 585bool tomoyo_domain_def(const unsigned char *buffer)
 586{
 587        const unsigned char *cp;
 588        int len;
 589
 590        if (*buffer != '<')
 591                return false;
 592        cp = strchr(buffer, ' ');
 593        if (!cp)
 594                len = strlen(buffer);
 595        else
 596                len = cp - buffer;
 597        if (buffer[len - 1] != '>' ||
 598            !tomoyo_correct_word2(buffer + 1, len - 2))
 599                return false;
 600        return true;
 601}
 602
 603/**
 604 * tomoyo_find_domain - Find a domain by the given name.
 605 *
 606 * @domainname: The domainname to find.
 607 *
 608 * Returns pointer to "struct tomoyo_domain_info" if found, NULL otherwise.
 609 *
 610 * Caller holds tomoyo_read_lock().
 611 */
 612struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname)
 613{
 614        struct tomoyo_domain_info *domain;
 615        struct tomoyo_path_info name;
 616
 617        name.name = domainname;
 618        tomoyo_fill_path_info(&name);
 619        list_for_each_entry_rcu(domain, &tomoyo_domain_list, list,
 620                                srcu_read_lock_held(&tomoyo_ss)) {
 621                if (!domain->is_deleted &&
 622                    !tomoyo_pathcmp(&name, domain->domainname))
 623                        return domain;
 624        }
 625        return NULL;
 626}
 627
 628/**
 629 * tomoyo_const_part_length - Evaluate the initial length without a pattern in a token.
 630 *
 631 * @filename: The string to evaluate.
 632 *
 633 * Returns the initial length without a pattern in @filename.
 634 */
 635static int tomoyo_const_part_length(const char *filename)
 636{
 637        char c;
 638        int len = 0;
 639
 640        if (!filename)
 641                return 0;
 642        while ((c = *filename++) != '\0') {
 643                if (c != '\\') {
 644                        len++;
 645                        continue;
 646                }
 647                c = *filename++;
 648                switch (c) {
 649                case '\\':  /* "\\" */
 650                        len += 2;
 651                        continue;
 652                case '0':   /* "\ooo" */
 653                case '1':
 654                case '2':
 655                case '3':
 656                        c = *filename++;
 657                        if (c < '0' || c > '7')
 658                                break;
 659                        c = *filename++;
 660                        if (c < '0' || c > '7')
 661                                break;
 662                        len += 4;
 663                        continue;
 664                }
 665                break;
 666        }
 667        return len;
 668}
 669
 670/**
 671 * tomoyo_fill_path_info - Fill in "struct tomoyo_path_info" members.
 672 *
 673 * @ptr: Pointer to "struct tomoyo_path_info" to fill in.
 674 *
 675 * The caller sets "struct tomoyo_path_info"->name.
 676 */
 677void tomoyo_fill_path_info(struct tomoyo_path_info *ptr)
 678{
 679        const char *name = ptr->name;
 680        const int len = strlen(name);
 681
 682        ptr->const_len = tomoyo_const_part_length(name);
 683        ptr->is_dir = len && (name[len - 1] == '/');
 684        ptr->is_patterned = (ptr->const_len < len);
 685        ptr->hash = full_name_hash(NULL, name, len);
 686}
 687
 688/**
 689 * tomoyo_file_matches_pattern2 - Pattern matching without '/' character and "\-" pattern.
 690 *
 691 * @filename:     The start of string to check.
 692 * @filename_end: The end of string to check.
 693 * @pattern:      The start of pattern to compare.
 694 * @pattern_end:  The end of pattern to compare.
 695 *
 696 * Returns true if @filename matches @pattern, false otherwise.
 697 */
 698static bool tomoyo_file_matches_pattern2(const char *filename,
 699                                         const char *filename_end,
 700                                         const char *pattern,
 701                                         const char *pattern_end)
 702{
 703        while (filename < filename_end && pattern < pattern_end) {
 704                char c;
 705                int i;
 706                int j;
 707
 708                if (*pattern != '\\') {
 709                        if (*filename++ != *pattern++)
 710                                return false;
 711                        continue;
 712                }
 713                c = *filename;
 714                pattern++;
 715                switch (*pattern) {
 716                case '?':
 717                        if (c == '/') {
 718                                return false;
 719                        } else if (c == '\\') {
 720                                if (filename[1] == '\\')
 721                                        filename++;
 722                                else if (tomoyo_byte_range(filename + 1))
 723                                        filename += 3;
 724                                else
 725                                        return false;
 726                        }
 727                        break;
 728                case '\\':
 729                        if (c != '\\')
 730                                return false;
 731                        if (*++filename != '\\')
 732                                return false;
 733                        break;
 734                case '+':
 735                        if (!isdigit(c))
 736                                return false;
 737                        break;
 738                case 'x':
 739                        if (!isxdigit(c))
 740                                return false;
 741                        break;
 742                case 'a':
 743                        if (!tomoyo_alphabet_char(c))
 744                                return false;
 745                        break;
 746                case '0':
 747                case '1':
 748                case '2':
 749                case '3':
 750                        if (c == '\\' && tomoyo_byte_range(filename + 1)
 751                            && strncmp(filename + 1, pattern, 3) == 0) {
 752                                filename += 3;
 753                                pattern += 2;
 754                                break;
 755                        }
 756                        return false; /* Not matched. */
 757                case '*':
 758                case '@':
 759                        for (i = 0; i <= filename_end - filename; i++) {
 760                                if (tomoyo_file_matches_pattern2(
 761                                                    filename + i, filename_end,
 762                                                    pattern + 1, pattern_end))
 763                                        return true;
 764                                c = filename[i];
 765                                if (c == '.' && *pattern == '@')
 766                                        break;
 767                                if (c != '\\')
 768                                        continue;
 769                                if (filename[i + 1] == '\\')
 770                                        i++;
 771                                else if (tomoyo_byte_range(filename + i + 1))
 772                                        i += 3;
 773                                else
 774                                        break; /* Bad pattern. */
 775                        }
 776                        return false; /* Not matched. */
 777                default:
 778                        j = 0;
 779                        c = *pattern;
 780                        if (c == '$') {
 781                                while (isdigit(filename[j]))
 782                                        j++;
 783                        } else if (c == 'X') {
 784                                while (isxdigit(filename[j]))
 785                                        j++;
 786                        } else if (c == 'A') {
 787                                while (tomoyo_alphabet_char(filename[j]))
 788                                        j++;
 789                        }
 790                        for (i = 1; i <= j; i++) {
 791                                if (tomoyo_file_matches_pattern2(
 792                                                    filename + i, filename_end,
 793                                                    pattern + 1, pattern_end))
 794                                        return true;
 795                        }
 796                        return false; /* Not matched or bad pattern. */
 797                }
 798                filename++;
 799                pattern++;
 800        }
 801        while (*pattern == '\\' &&
 802               (*(pattern + 1) == '*' || *(pattern + 1) == '@'))
 803                pattern += 2;
 804        return filename == filename_end && pattern == pattern_end;
 805}
 806
 807/**
 808 * tomoyo_file_matches_pattern - Pattern matching without '/' character.
 809 *
 810 * @filename:     The start of string to check.
 811 * @filename_end: The end of string to check.
 812 * @pattern:      The start of pattern to compare.
 813 * @pattern_end:  The end of pattern to compare.
 814 *
 815 * Returns true if @filename matches @pattern, false otherwise.
 816 */
 817static bool tomoyo_file_matches_pattern(const char *filename,
 818                                        const char *filename_end,
 819                                        const char *pattern,
 820                                        const char *pattern_end)
 821{
 822        const char *pattern_start = pattern;
 823        bool first = true;
 824        bool result;
 825
 826        while (pattern < pattern_end - 1) {
 827                /* Split at "\-" pattern. */
 828                if (*pattern++ != '\\' || *pattern++ != '-')
 829                        continue;
 830                result = tomoyo_file_matches_pattern2(filename,
 831                                                      filename_end,
 832                                                      pattern_start,
 833                                                      pattern - 2);
 834                if (first)
 835                        result = !result;
 836                if (result)
 837                        return false;
 838                first = false;
 839                pattern_start = pattern;
 840        }
 841        result = tomoyo_file_matches_pattern2(filename, filename_end,
 842                                              pattern_start, pattern_end);
 843        return first ? result : !result;
 844}
 845
 846/**
 847 * tomoyo_path_matches_pattern2 - Do pathname pattern matching.
 848 *
 849 * @f: The start of string to check.
 850 * @p: The start of pattern to compare.
 851 *
 852 * Returns true if @f matches @p, false otherwise.
 853 */
 854static bool tomoyo_path_matches_pattern2(const char *f, const char *p)
 855{
 856        const char *f_delimiter;
 857        const char *p_delimiter;
 858
 859        while (*f && *p) {
 860                f_delimiter = strchr(f, '/');
 861                if (!f_delimiter)
 862                        f_delimiter = f + strlen(f);
 863                p_delimiter = strchr(p, '/');
 864                if (!p_delimiter)
 865                        p_delimiter = p + strlen(p);
 866                if (*p == '\\' && *(p + 1) == '{')
 867                        goto recursive;
 868                if (!tomoyo_file_matches_pattern(f, f_delimiter, p,
 869                                                 p_delimiter))
 870                        return false;
 871                f = f_delimiter;
 872                if (*f)
 873                        f++;
 874                p = p_delimiter;
 875                if (*p)
 876                        p++;
 877        }
 878        /* Ignore trailing "\*" and "\@" in @pattern. */
 879        while (*p == '\\' &&
 880               (*(p + 1) == '*' || *(p + 1) == '@'))
 881                p += 2;
 882        return !*f && !*p;
 883 recursive:
 884        /*
 885         * The "\{" pattern is permitted only after '/' character.
 886         * This guarantees that below "*(p - 1)" is safe.
 887         * Also, the "\}" pattern is permitted only before '/' character
 888         * so that "\{" + "\}" pair will not break the "\-" operator.
 889         */
 890        if (*(p - 1) != '/' || p_delimiter <= p + 3 || *p_delimiter != '/' ||
 891            *(p_delimiter - 1) != '}' || *(p_delimiter - 2) != '\\')
 892                return false; /* Bad pattern. */
 893        do {
 894                /* Compare current component with pattern. */
 895                if (!tomoyo_file_matches_pattern(f, f_delimiter, p + 2,
 896                                                 p_delimiter - 2))
 897                        break;
 898                /* Proceed to next component. */
 899                f = f_delimiter;
 900                if (!*f)
 901                        break;
 902                f++;
 903                /* Continue comparison. */
 904                if (tomoyo_path_matches_pattern2(f, p_delimiter + 1))
 905                        return true;
 906                f_delimiter = strchr(f, '/');
 907        } while (f_delimiter);
 908        return false; /* Not matched. */
 909}
 910
 911/**
 912 * tomoyo_path_matches_pattern - Check whether the given filename matches the given pattern.
 913 *
 914 * @filename: The filename to check.
 915 * @pattern:  The pattern to compare.
 916 *
 917 * Returns true if matches, false otherwise.
 918 *
 919 * The following patterns are available.
 920 *   \\     \ itself.
 921 *   \ooo   Octal representation of a byte.
 922 *   \*     Zero or more repetitions of characters other than '/'.
 923 *   \@     Zero or more repetitions of characters other than '/' or '.'.
 924 *   \?     1 byte character other than '/'.
 925 *   \$     One or more repetitions of decimal digits.
 926 *   \+     1 decimal digit.
 927 *   \X     One or more repetitions of hexadecimal digits.
 928 *   \x     1 hexadecimal digit.
 929 *   \A     One or more repetitions of alphabet characters.
 930 *   \a     1 alphabet character.
 931 *
 932 *   \-     Subtraction operator.
 933 *
 934 *   /\{dir\}/   '/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/
 935 *               /dir/dir/dir/ ).
 936 */
 937bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename,
 938                                 const struct tomoyo_path_info *pattern)
 939{
 940        const char *f = filename->name;
 941        const char *p = pattern->name;
 942        const int len = pattern->const_len;
 943
 944        /* If @pattern doesn't contain pattern, I can use strcmp(). */
 945        if (!pattern->is_patterned)
 946                return !tomoyo_pathcmp(filename, pattern);
 947        /* Don't compare directory and non-directory. */
 948        if (filename->is_dir != pattern->is_dir)
 949                return false;
 950        /* Compare the initial length without patterns. */
 951        if (strncmp(f, p, len))
 952                return false;
 953        f += len;
 954        p += len;
 955        return tomoyo_path_matches_pattern2(f, p);
 956}
 957
 958/**
 959 * tomoyo_get_exe - Get tomoyo_realpath() of current process.
 960 *
 961 * Returns the tomoyo_realpath() of current process on success, NULL otherwise.
 962 *
 963 * This function uses kzalloc(), so the caller must call kfree()
 964 * if this function didn't return NULL.
 965 */
 966const char *tomoyo_get_exe(void)
 967{
 968        struct file *exe_file;
 969        const char *cp;
 970        struct mm_struct *mm = current->mm;
 971
 972        if (!mm)
 973                return NULL;
 974        exe_file = get_mm_exe_file(mm);
 975        if (!exe_file)
 976                return NULL;
 977
 978        cp = tomoyo_realpath_from_path(&exe_file->f_path);
 979        fput(exe_file);
 980        return cp;
 981}
 982
 983/**
 984 * tomoyo_get_mode - Get MAC mode.
 985 *
 986 * @ns:      Pointer to "struct tomoyo_policy_namespace".
 987 * @profile: Profile number.
 988 * @index:   Index number of functionality.
 989 *
 990 * Returns mode.
 991 */
 992int tomoyo_get_mode(const struct tomoyo_policy_namespace *ns, const u8 profile,
 993                    const u8 index)
 994{
 995        u8 mode;
 996        struct tomoyo_profile *p;
 997
 998        if (!tomoyo_policy_loaded)
 999                return TOMOYO_CONFIG_DISABLED;
1000        p = tomoyo_profile(ns, profile);
1001        mode = p->config[index];
1002        if (mode == TOMOYO_CONFIG_USE_DEFAULT)
1003                mode = p->config[tomoyo_index2category[index]
1004                                 + TOMOYO_MAX_MAC_INDEX];
1005        if (mode == TOMOYO_CONFIG_USE_DEFAULT)
1006                mode = p->default_config;
1007        return mode & 3;
1008}
1009
1010/**
1011 * tomoyo_init_request_info - Initialize "struct tomoyo_request_info" members.
1012 *
1013 * @r:      Pointer to "struct tomoyo_request_info" to initialize.
1014 * @domain: Pointer to "struct tomoyo_domain_info". NULL for tomoyo_domain().
1015 * @index:  Index number of functionality.
1016 *
1017 * Returns mode.
1018 */
1019int tomoyo_init_request_info(struct tomoyo_request_info *r,
1020                             struct tomoyo_domain_info *domain, const u8 index)
1021{
1022        u8 profile;
1023
1024        memset(r, 0, sizeof(*r));
1025        if (!domain)
1026                domain = tomoyo_domain();
1027        r->domain = domain;
1028        profile = domain->profile;
1029        r->profile = profile;
1030        r->type = index;
1031        r->mode = tomoyo_get_mode(domain->ns, profile, index);
1032        return r->mode;
1033}
1034
1035/**
1036 * tomoyo_domain_quota_is_ok - Check for domain's quota.
1037 *
1038 * @r: Pointer to "struct tomoyo_request_info".
1039 *
1040 * Returns true if the domain is not exceeded quota, false otherwise.
1041 *
1042 * Caller holds tomoyo_read_lock().
1043 */
1044bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r)
1045{
1046        unsigned int count = 0;
1047        struct tomoyo_domain_info *domain = r->domain;
1048        struct tomoyo_acl_info *ptr;
1049
1050        if (r->mode != TOMOYO_CONFIG_LEARNING)
1051                return false;
1052        if (!domain)
1053                return true;
1054        list_for_each_entry_rcu(ptr, &domain->acl_info_list, list,
1055                                srcu_read_lock_held(&tomoyo_ss)) {
1056                u16 perm;
1057                u8 i;
1058
1059                if (ptr->is_deleted)
1060                        continue;
1061                /*
1062                 * Reading perm bitmap might race with tomoyo_merge_*() because
1063                 * caller does not hold tomoyo_policy_lock mutex. But exceeding
1064                 * max_learning_entry parameter by a few entries does not harm.
1065                 */
1066                switch (ptr->type) {
1067                case TOMOYO_TYPE_PATH_ACL:
1068                        data_race(perm = container_of(ptr, struct tomoyo_path_acl, head)->perm);
1069                        break;
1070                case TOMOYO_TYPE_PATH2_ACL:
1071                        data_race(perm = container_of(ptr, struct tomoyo_path2_acl, head)->perm);
1072                        break;
1073                case TOMOYO_TYPE_PATH_NUMBER_ACL:
1074                        data_race(perm = container_of(ptr, struct tomoyo_path_number_acl, head)
1075                                  ->perm);
1076                        break;
1077                case TOMOYO_TYPE_MKDEV_ACL:
1078                        data_race(perm = container_of(ptr, struct tomoyo_mkdev_acl, head)->perm);
1079                        break;
1080                case TOMOYO_TYPE_INET_ACL:
1081                        data_race(perm = container_of(ptr, struct tomoyo_inet_acl, head)->perm);
1082                        break;
1083                case TOMOYO_TYPE_UNIX_ACL:
1084                        data_race(perm = container_of(ptr, struct tomoyo_unix_acl, head)->perm);
1085                        break;
1086                case TOMOYO_TYPE_MANUAL_TASK_ACL:
1087                        perm = 0;
1088                        break;
1089                default:
1090                        perm = 1;
1091                }
1092                for (i = 0; i < 16; i++)
1093                        if (perm & (1 << i))
1094                                count++;
1095        }
1096        if (count < tomoyo_profile(domain->ns, domain->profile)->
1097            pref[TOMOYO_PREF_MAX_LEARNING_ENTRY])
1098                return true;
1099        if (!domain->flags[TOMOYO_DIF_QUOTA_WARNED]) {
1100                domain->flags[TOMOYO_DIF_QUOTA_WARNED] = true;
1101                /* r->granted = false; */
1102                tomoyo_write_log(r, "%s", tomoyo_dif[TOMOYO_DIF_QUOTA_WARNED]);
1103#ifndef CONFIG_SECURITY_TOMOYO_INSECURE_BUILTIN_SETTING
1104                pr_warn("WARNING: Domain '%s' has too many ACLs to hold. Stopped learning mode.\n",
1105                        domain->domainname->name);
1106#endif
1107        }
1108        return false;
1109}
1110